1. Field of the Invention
The invention generally relates to fifth wheel assemblies of the type having a vertically oriented king pin and employed in coupling tractor-trailer rigs, and more particularly to a safety device adapted to respond to the failure of a king pin or its latching mechanism for safely coupling the tractor-trailer rig in an alternate configuration.
2. Description of the Prior Art
As can be appreciated by those familiar with the maintenance and operation of tractor-trailer rigs, each of the fifth wheel assemblies employed for coupling a tractor-trailer rig usually includes a first wear plate rigidly mounted on a trailer, having a king pin projected therefrom, and a second wear plate pivotally mounted on the tractor, for receiving the first wear plate in contiguous relation, including a latching mechanism for capturing the king pin, whereby coupling of the trailer with the tractor is achieved by mating the wear plates with the king pin being disposed in a captured relationship with the latching mechanism.
Of course, as a consequence of operation of the rig, the king pin frequently is subjected to substantial wear and fatigue, the extent of which often remains undetected. In instances where a cargo of substantial value must be transported, utilizing tractor-trailer rigs, a great deal of interest has been focused on the potential loss which may be occasioned through failure of the king pins or their latching mechanisms employed in coupling the rigs.
For the purposes of the instant invention, it is to be understood that the term "failure", as it refers to king pins, is assumed to mean deformed and/or separated.
Therefore, it should be apparent that one of the unsolved problems facing those engaged in the manufacture and use of tractor-trailer rigs is that of providing a safety device which is economic, practical, easy to install aboard existing rigs, efficient in operation, and capable of responding to the failure of a king pin or its latching mechanism for achieving a coupling of a trailer with a tractor in an alternative configuration.
It is, therefore, a general purpose of the instant invention to provide a practical, economic, simplified and efficient safety device for coupling a tractor-trailer rig in an alternate configuration in response to the failure of the king pin relied upon for coupling the trailer with the tractor in a first configuration.